Electric wire coupling



Jan. 3, 1956 K. J. KNUDSEN 2,729,800

ELECTRIC WIRE COUPLING Filed April 25, 1953 @is 22 50 33 19 ai 26 25 23 2O IN VENTOR ATTORNEY5 Unite Patent O ELECTRIC Wim: coUPLlNG Knud J; Knudsen, Naugatuck, Conn., assigner to The Lewis Engineering Company, Naugatuck, Conn., a cor-A poration of Connecticut Application April 23, 1953, Serial No. 350,646

8 Claims. (Cl. 339-188) This invention relates to electricalconnectors or couplings, and more particularly to a connector of the type havingbutting contacts, which is adapted to connect together two ends of an electrical line or wire.

An object of the invention is to provide an improved line connector of the type having butting contacts arranged'to prevent separation of the contacts if the line is subjected to a longitudinal pull, which connector is simple in construction with few parts, and economical to fabricate.

Another object of the invention is to provide an improved line connector as above set forth, which is reliable in use, and efficient in conducting the current. of the line.

Still another object of the invention is to provide an improved electrical connector in accordance with the above, which is small in size and compact, and may be readily and easily operated to connect or disconnect tlie lines or wires.

A feature of the invention is the provision of a line coupling or connector asabove set forth, which may be readily serviced when necessary, and in which the various parts may be replaced, if and when requiredwith a minimum of time and trouble.

Other features and advantages will hereinafter appear.

In the accompanying drawings:

Figure 1 is a side elevational view of the improved coupling or connector of the invention.

Fig. 2 is an axial sectional view ofthe connector.

Fig. 3 is an-axialsectional View, with some ofthe components shown in elevation, the twoemain parts of the connector being separated.

Referring to the drawing, the improved electricallconnector of this invention comprises a casing which is preferably formed of two drawn shells telescoping each other, an outer shell 11 and an inner shell 12. Fastening means is provided for detachably securing the shells to each other, in the form of bayonet slots 13 andbayonet pins 14 as is usual in connector constructions.

The couplingV or connector of'this invention is of the` type having butting contacts with an arrangement whereby a longitudinal pull on the electrical'lines or wires will not separate the contacts. Referringto Fig. 2, the connector joins and electrically connects together the ends of lines or wires 15 andf16,' which pass into the respective remote: ends .ofv the casing.. shells. 11.. and 12.

Within the casing 10 .there is provided a pair of abutting contacts. 17 and 18,.. electrically. connectedrespectively to the lines 15 and 16.

In accordance with the present invention an improved andy simplified connector construction is-provided which is simple, has few parts, is economical to fabricate, reliable in use and efiicient in conducting the current passing through the lines 15 and 16. The connector is also small in size and compact, and may be readily operated to connect the lines 15 and 16 or disconnect them from each other.

In accomplishing these objects the abutting contacts 17 and 18 are made tubular, and the contact 17 is made ICC to telescope with. a. member 19 secured to the line. 15, whereby the contact 17 is axially movable in the casing 10 while the member 19 and line 15 remain stationary. Thus avery simple structure is involved, in producing the floating contact 17, which structure is not likely to get outof order and may be readily serviced whennecessary.

The tubular contact 18-has, extending around it, an insulating bushing -2.0 which is held in place by outturned end flanges 21 and 22 of the contact, the end flange 21 constituting'the abutting contactingsurface of the contact 18 and presenting aerelatively large contact area.

The tubular contact 17. also carries .an insulating bushing 23 and has an outturned'end lange 24 which positions the bushing 23 and provides an abutting contact surface engageable with the outturned flange 21 of the contact 18. Relatively large cooperable areas of contact are thereby provided byl the outturned flanges 21 and 24-of the contacts 18 and 17.

The` tubular contacts 17 has a crimp 25 intermediate its ends, constitutinga second outturned. ange which securely holds the bushing 23 in the desired position on the contact.

To the left of the crimp 25, as-viewed in Fig. 2the contact 17 has a telescoping portion 26'havinglongitudinal slots127 whereby the portion 26 may be biased to continually press against the telescoping member 19 which extends into the portion 26.

The telescoping member 19 is insulatedly mountedin the shell 11, carrying aninsulating bushing 2S, and said member has an outturnedend flange 29 anda crimp 30 by which the bushing 28 issecured in place.

The lines 1S and 16, Fig. 2, haveconductors 31 and 32 respectively which-extend intothe member 19 and the contact 18, said conductors beingsoldered to these parts as'shownand well understood in the art.

For the purpose ofv yieldably holding Vthe movable contact 17 in engagement withthe contact 18 a helical expansion coil spring 33 is provided, extending aroundthe members 19 and 26. and engaging the bushings 23 and 28, and the spring 33 isinsulatedfby the bushings from the telescoping members19, 26 and the contact 17.

The bushings 20, 23 and 2S all fit within and are positionedby the inner walls of the casing 10 as shown in Figs. 2 and 3and centralize .the contacts 1'7 and 18 in the casing, insulating them from the shells 11 andk 12.

Referring toFigi. 3n it will be observed that when the shellsll and 12 are disconnected from each other the spring 33 expands, shifting the movable contact 17, bushing 23 and telescoping portion 26 to the right as viewed in the figure, to an extended position. The telescoplng members19 and. 26will remain in engagement with each other, however, and .whenthe shellsl 11 and 12 arebrought together. again thespring 33 will becompressed by movementof the. contact 17"to the left, and said contact will thereby. be securely. held in engagement withthe contact 18. It will'be. understood that the action of the spring 33`in holding ,the.contact.17 in engagement with the contact.18 isindependent of any longitudinalpull on the lines 15 andl, by virtue of the telescoping arrangement of the members 19' and 26.

The movable assembly constituted by the contact 17, bushing123 an'd'telescoping portion 26 may be thought ot asap'lunger which' telescopically engages the member 19, the latter being in the form of a contact stud. The electrical connection between the stud 19 and the contact 17 is established by the sliding engagement between the telescoping members 19 and 26, such engagement being under continual pressure due to the bias of the slotted member 26. The sliding surfaces of the members 19 and 26 may be silver plated, if desired, where low resistivity is important.

Servicing of the connector of this invention, or replacement of the component parts may be readily effected. The bushing 2t) is slidably carried in the shell 12 and may be replaced by merely unsoldering it from the conductor 32 and soldering a new bushing and contact 13 to the conductor. The assembly comprising the telescoping members 19 and 26, the spring 33, the bushings 2.3 and 28 and the contact 17 is slidable out of the outer shell 11. The spring 33, contact 17, bushing 23 and telescoping portion 26 of the contact are readily removable from the member 19 for replacement without the necessity of tools. Replacement of the bushing 28 and telescoping member 19 is effected by unsoldering the member 19 from the conductor 31 and soldering a new telescoping member and bushing to the conductor. Obviously the shells 11 and 12 may be easily replaced if they should become damaged or otherwise rendered inoperative.

Variations and modifications may be made within the scope of the claims and portions of the improvements may be used without others.

I claim:

1. An electric connector for detachably connecting together two electric lines, comprising a tubular casing having an inwardly-extended shoulder adjacent one end; a pair of contacts in the casing, having abutting engagement with each other; means mounting one contact on the casing for movement toward and away from the other contact including a pair of telescoping metal members in the casing, slidable one on the other, said one contact being rigidly secured and electrically connected to one of the telescoping members and the other telescoping member being loosely carried in and engaging the shoulder of the casing, said shoulder preventing pull-out of said other member; resilient means normally holding said one contact in abutting engagement with the other contact, said means normally retaining said other telescoping member and shoulder in engagement and means electrically connecting the ends of the lines respectively to said other contact and to said other telescoping member.

2. The invention as deiined in claim l in which the casing comprises a pair of telescoping shells having means for detachably securing the shells to each other, one shell carrying said telescoping members and one contact, and the other shell carrying said other contact.

3. The invention as dened in claim 1 in which the said one of the telescoping members and the said one contact are tubular, and integral, said one member having a longitudinal slot and being biased to cause the portions thereof adjacent the slot to continually press against the other member.

4. The invention as defined iu claim 3 in which the said other telescoping member is tubular and has one line end extending into and secured to it, and in which the slotted telescoping member extends around the outside of said other telescoping member.

5. An electric connector for detachably connecting together two electric lines, comprising a casing; a pair of contacts in the casing, having abutting engagement with each other; means mounting one contact on the casing for movement toward and away from the other contact including a pair of telescoping metal members in the casing, slidable one on the other, said one contact being rigidly secured and electrically connected to one of the telescoping members and the other telescoping member being normally stationary in the casing; resilient means normally holding said one contact in abutting engagement with the other contact; and means electrically connecting the ends of the lines respectively to said other contact and to said other telescoping member, said telescoping members having insulating bushings extending around them and secured to end portions of the members, and said resilient means comprising an expansion coil spring disposed around the members and at its ends engaging the said bushings.

6. An electric connector for detachably connecting together two electric lines, comprising a casing; a pair of contacts in the casing, having abutting engagement with each other; means mounting one contact on the casing for movement toward and away from the other contact including a pair of telescoping metal members in the casing, slidable one on the other, said one contact being rigidly secured and electrically connected to one of the telescoping members and the other telescoping member being normally stationary in the casing; resilient means normally holding said one contact in abutting engagement with the other contact; means electrically connecting the ends of the lines respectively to said other contact and to said other telescoping member, said contacts comprising tubular parts provided with outturned end lianges which have the said abutting engagement; and insulating bushings extending around the tubular parts and disposed against the said end flanges and engaging the casing, said tubular parts having other outturned anges holding the bushings in position against the said end anges.

7. The invention as deiincd in claim 6 in which the said one telescoping member is tubular and connected with the said other outturned flange of the one tubular contact part.

8. An electric connector for detachably connecting together two electric lines, comprising a casing; a pair of contacts in the casing having abutting engagement with each other; means mounting one contact on the casing for movement toward and away from the other contact, including a pair of telescoping metal members in the casing, slidable one on the other, said one contact being rigidly secured and electrically connected to one of the telescoping members and the other telescoping members being normally stationary in the casing; resilient means normally holding said one contact in said abutting engagement with the other contact; means electrically connecting the ends of the lines respectively to said other contact and to said other telescoping member, said contacts comprising tubular parts provided with outturned end flanges which have the said abutting engagement; insulating bushings extending around the said contacts, disposed against the end ilanges thereof and engaging the casing, said tubular parts having other outturned llanges holding the bushings in position against the said end flanges and the said one telescoping member being tubular and integral with the said one tubular contact part; and an insulating bushing extending around the said other telescoping member, said casing being tubular and the inside walls thereof engaging and positioning all of said bushings.

References Cited in the tile of this patent UNITED STATES PATENTS 1,249,711 Berg Dec. 11, 1917 1,678,138 Douglas July 24, 1928 1,742,850 Douglas Jan. 7, 1930 FOREIGN PATENTS 334,235 Great Britain Sept. 1, 1930 

